#include<stdio.h>
#include<conio.h>
#include<math.h>
int uocchungln(int a, int b);
int main(){
	int a,b;
	printf("nhap vao hai so a,b: ");
	scanf("%d%d",&a,&b);
	printf("Uoc chung lon nhat la: %d",uocchungln(a,b));
	getch();
}
int uocchungln(int a, int b){
     while(a!=b){
     	if(a>b) a=a-b;
     	else b=b-a;
     }
     return a;
}
